Does Baptism wash away my sin?

Our listener asks, “My question is in regards to Bible verses such as Acts 22:16 and Acts 2:38 that seem to suggest a person has to be water baptized to go to heaven. I believe that a person does not have to be water baptized to go to Heaven because of incidences such as the thief on the cross. However, how do I explain these verses to others when I’m trying to tell them all they have to do is Believe in Jesus and verses such as these arise when having a conversation?”